The ADC hardware trigger, soft triggers the acquisition for the rest of the CAMAC crate which happens to be the TD2 & 4s for the readout of the whole CBPM system (further down the timing line) and the magnet system - so definitely don't unplug.
The gate delay and width can however be adjusted as long as the gate is sufficiently wide for the others to trigger.
There is a 'T' in the trigger line. The gate can be monitored on an oscilloscope using 1MOhm impedance (effectively passive to 50 Ohm).
Setup
After breaking and fixing readout for everyone else, adjust gate width and delay to overlap with PMT pulses from each detector
Raised voltage slowly during beam time on each pmt until between 500mV - 1V pulses were seen (from experience).
900V was sufficient and there was strong signal in both at 1kV.
Timing is shown in the picture below.
Data is in dat/general/20150616_detector_gate_setup/
Green is detector 2 (new location further upstream)
Yellow is detector 1 (laserwire location)
Blue is the gate signal - note ringing oscillations are from mismatch into 1MOhm impedance